Fold-up tower section



Dec. 5, 1961 J. E. HARVEY, JR 3,011,586

FOLD-UP TOWER SECTION Filed Oct. 7, 1958 3 Sheets-Sheet 1 INVENTOR, JOHN E HA1? v x A TTOH/VE).

Dec. 5, 1961 J. E. HARVEY, .111 3,011,586

FOLD-UP TOWER SECTION Filed Oct. 7, 1958 5 Sheets-Sheet 2 JNVENTOR, JOHN E. HARVEY A TTORNEX Dec. 5, .1961 J. E. HARVEY, JR 3,011,586

FOLD-UP TOWER SECTION Filed Oct. 7, 1958 5 Sheets-Sheet 3 FIG. 8

INVENTOR, JOHN 5. HA? VEX BWMW A 7' TORNE )1 United States Patent 3,011,586 FOLD-UP TOWER SECTION John E. Harvey, In, West Long Branch, N.J., assignor to the United States of America as represented by the Secretary of the Army Filed Oct. 7, 1958, Ser. No. 766,157 3 Claims. (Cl. 182-115) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by and for the Government for governmental purposes without the payment to me of any royalty thereon.

The invention relates to a portable tower structure for supporting an antenna for very high frequency communication systems.

It more particularly relates to a portable tower structure for supporting an antenna for very high frequency systems as it is related to military utilization. v

.In the realm of military utilization, communication systems must possess'the characteristic of portability. It must be capable of being moved into an area and set up for operation as quickly as possible. It must further 'be capable of being disassembled and moved to other areas as dictated by the flow of the tides of battle.

i It is also essential that maximum performanceof such asystem be obtained at all times while it is in operation. Very high frequency communication systems have a range of operation limited substantially by the line of sight distance. The line of sight distance depends on the elevation of the points between which the line of sight is taken. The higher the points are above the surrounding terrain the greater will be the line of sight distance. Consequently, the higher the elevation of the transmitting and receiving antennas, the greater will be the distance over which communication will be possible. In the past, antennas for portable communication systoms of the nature referred to have been raised on masts, maintained in vertical position by the use of guy wires. The magnitude of elevation possible with the use of a mast has been very limited, and this has imposed a limiting effect on the range of communication.

The mast type of antenna support has imposed further complications. Very high frequency antennas require servicing and adjustment while in the elevated position.

When the antenna is supported by a mast it has not always been possible to make such adjustments.

The present invention has for an object to provide a 'tower for supporting a very high frequency antenna in a higher elevated position than possible with a mast type support.

Another object of the invention is to provide a portable tower support for very high frequency antennas that may be quickly moved and erected in any desired position. Still another object of the invention is to provide a portable tower for supporting a veryhigh frequency antenna in a higher elevated position than possible with a mast type support and at the sametime provide for accessibility to the antenna while in its elevated position.

Another object of the invention'is to provide a tower section, incorporating features which provide for compactness when disassembled, for ease of handling and erection into a tower structure and for the accessibility limits thereof.

Other objects of the invention will appear from a consideration of the following description and drawings.

to the upper While the invention is particularly designed for the support of very high frequency antennas, it isflby no means limited thereto. It may be used for otherpurposes, as for example, for supporting. an observation plat} form in an elevated position from which the surrounding terrain may be surveyed.

FIG. 1 is an elevational view of a tower structure incorporating a plurality of tower sections.

FIG. 2 is a perspective view of a tower section according to the invention.

FIG. 3 is a perspective view of a platform forming a component of the tower section.

FIG. 4 is a fragmentary perspective view of the sides of the tower section, folded for transportation or storage.

FIG. 5 is a perspective view of the tower section, partially unfolded, showing the manner in which the side members may be folded on each other.

FIG. 6 is a perspective view of a ladder, which also functions in the tower structure as an internal strut member.

FIG. 7 is a perspective view of the removable strut members which, when assembled in the tower section, form a side of the tower section.

FIG. 8 is a detail in partial section showing the ends of the posts and the manner in which they are joined together. FIG. 9 is a sectional view of a detail of the lower end of the tower posts of the lower tower section and base member.-

FIG. 10 is a partial sectional view of a hook type fas'tem ing means suitable for connecting the removable struts to other tower members. a

FIG. 11 is a' plan View of a base member for supporting the lower end of the tower. FIG. 1 illustrates a tower constructed of a plurality of tower sections 10, one mounted upon the other to a prescribed height. The broken lines, immediately below the top sleeve 26, are for the purpose of showing that a plurality of tower sections 10 are used. The top'of FIG. 1 is the top of one section 10 and the bottom of FIG. 1 is the bottom of another section 10. Any number of sections 10 can be inserted between the top and bottom sections 10. The height of the tower is limited onlyby the weight supporting strength of the separate tower sections, particularly the members 21, 22, 31 and 32. The posts and strut members may be fabricated from tubular steel or aluminum alloy. The upper ends of the posts 21, 22, 31 and 32 of each section 10 are provided with brackets 9. The brackets 9 are clamped or otherwise fixed to the posts and are provided with apertures for receiving the upper ends of guys 8. The lower ends of the guys 8 may be connected to anchor means (not shown) buried or otherwise fixed to the ground.

The lower end of the tower section 10 may be seated upon abase member 6 such as is illustrated in FIG. 11. The base member 6 may be constructed as a rectangular frame of timber, providing a large bearing surface in contact with the ground, whereby the weight of the tower will be distributed over as great an area as possible. As shown in FIG. 9, the frame member 6 is further provided with pins which project a short distance into the 'frame and extend a short distance above the frame. The pins are spaced at appropriate distances to be received by the lower end of the tower section.

A tubular sleeve 26 embraces each of the pins. A spreader member 23A connects the sleeves 26 and extends between the posts 21 and 22. Another spreader 33A connects the other two sleeves and extends between posts 31 and 32. As illustrated in FIG. 11, the Spreaders 23A and 33A are embraced by sleeve members connected frame work for maintaining the lower ends of the posts '21, 22 31 and 32 at their proper spaced positions. The diagonal struts 66A also provide a means for anchoring the lower end of a ladder 70 to be later described.

h The pins extend through the sleeves 26 and a shorttower section is secured to the base member.

The upper ends of the posts 21, 22, 31 and 32, as shown in FIG; 1, engage the lower ends of the posts 21, 22, 31 and 32 of the section above. FIG. 8 discloses a detail of the connection including a transverse tapered bore for receiving a slightly tapered pin that may be provided for securing the sections together.

The upper end of the upper tower section 10 mounts platform 3 having spaced means to receive the upper ends'of the posts 21, 22, 31 and 32. The platform may be provided with an-access opening through the center and the necessary hardware for mounting an antenna thereon; The exact structure of the platform 3 forms no part of the present invention. Any suitable structure for the purpose will suffice.

The desirable features, which enhance the portability of the tower and make it especially suitable to support an antenna, reside in the structure of the individual tower sections 10, shown in greater detail in FIG. 2.

The tower section 10 is composed of two side members 20 and 30, each similarly constructed. The sides 20 and 30 each are formed of post members 21, 22, 31 and 32, fabricated from tubular stock. The upper ends of the posts 21 and 22 of side 20 are embraced by tubular sleeves 26 a short distance from the ends thereof. The posts 21 and 22 extend through the sleeves 26 and form pin members to which corresponding posts of other sections may be secured. As shown in FIG. 8 the upper ends of the posts are transversed by a tapered bore for the reception of a tapered pin, for the locking of the sections together in assembled relation.

The tubular sleeves 26on the posts 21 and 22 are joined together by spreader members 23 extending between and spacing the posts 21 and 22 the required distance.

The posts 21 and 22 are embraced at their lower ends by tubular sleeves 26 which provide sockets for the re-' ception of the tubular posts of the lower section. As shown in FIG. 8, the lower end of the posts 21, 22 extend approximately half way through the sleeve 26. The sleeve is provided with a transverse tapered bore to receive a tapered locking pin. The sleeves 26 on the posts 21 and 22 are joined together by spreaders 24 to hold the lower ends in their proper spaced relation.

The posts are embraced between their ends by sleeves 26 welded or otherwise fixed thereto. The sleeves 26 on one post are joined to sleeves on the opposite post by diagonal struts 25. a

The side 30 is similarly constructed, having posts 31 and 32 joined at their ends by spreaders 33 and 34 and by diagonal struts 35 at points between the ends thereof.

The sides thus formed are truss-like members and constitute the first and third sides of the tower section.

A second side of the tower section 40 is formed by diagonally arranged strut members 45. The posts 22 and 32 are each embraced by sleeves 36 and 46 between collars 37 and 47 arranged at predetermined points between the ends of the posts. The sleeves 36' and 46 are rotatable upon the posts the positions between. the collars 37 and 47. 'The'collars 37am 47 are fixed to the posts by any suitable means as by welding or brazing and operate to prevent longi- 22 and 32 respectively in tudinal motion of the sleeves 36 and 46. The sleeves I V are joined to the sleeves on the opposite post by a diagonal strut member 45 to form the second side of the tower section. Because the sleeves/t6 are rotatable on. the posts the first and third sides'are foldable as shown in FIG. 5. The side 20 may be folded against oneside of the struts 45 and the other'side 30 may be folded against the otherside 0f the struts 45 (see FIG. 4)

The fourth side of the tower section is formed by the removable struts 55. The struts 55 have their ends connected to snap-on hooks that may be of the character shown in FIG. 10. The posts are provided with spaced collars 57 (see FIG. 2) attached thereto as by welding or brazing or the like. The snap-on hooks 56 embrace the posts 21 and 31 at a point between the spaced collars 57. When in position, the removable struts operate to form the fourth side of the tower sec tion. The collars 57 operate to prevent movement of the snap-on hooks 56 longitudinally of the posts.

The tower section 10 is completed by a top side, designated a landing or platform 60 separately constructed and adapted to snap-on in place to give the structure rigidity against shearing forces tending to distort the tower into a diamond shape cross-section. I

The platform 60 is shown in detail in FIG. 3. It is composed of a pair of spreader members 61 and 62 each having snap-on hooks fixed to the ends thereof. The spreader members 61 and 62 are spaced apart by spreader members 64 and 65 welded or otherwise attached at their ends to the spreader members 61 and 62. The four spreader members 61, 62, 64 and 65 form the outer boundary of the landing and platform 60. Strut members 66 extend from a point on each of said spreader members 61 and 62 midway between the ends thereof to a point on each of said spreader members 64 and 65 at a point midway between their ends. The struts may be attached to the spreaders in any suitable manner. The struts form the boundaries framing an access opening through the platform 60. f

The space between the spreaders and strut members is spanned by an expanded metal grating, tack welded to the spreaders and the struts to form a flooring for the platform. An additional hook 68 is welded or otherwise attached to the spreaders 64 and 65 and is adapted to engage over the midpoint of the spreader members 23 and 33 of the sides 20 and 30.

As illustrated in FIG. 2, the books on the ends of the spreader members 61 and 62 and the hooks on the spreader members 64 and 65 engage and embrace the spreader members 23 and 33 when the platform is in place and they operate to support the landing in place. The landing, when in place, operates to strengthen the tower section against horizontal shearing forces that would otherwise distort the structure.

As shown in FIGS. 1 and 2, a ladder 70 is provided with snapon hooks 71 at the ends thereof. The ladder has a length adapted to extend between landings of the tower sections, the snap-on hooks engaging and embracing the struts 66. The ladder, so arranged, extends diagonally of the tower section and operates as an internal strut to form, with the side of the tower section, a truss-like means. The ladder also provides a means by which the upper-most level of the tower may be reached with comparative ease, whereby the antenna mounted on the upper platform is made accessible while in place.

The tower section as thus far described includes the three folded sides portion, the four removable strut members 55, a platform 60 and a ladder 70. The guying means, the upper platform and the base member are separate and in addition to the enumerated parts that make up the tower structure. r

The small number of separately handled parts makes for speedy erection and dismantling of the tower structure. The provisions for pivoting the sides 20 and 30 on the struts 45 about the axis" of the posts 21 and 31 without the addition of additional parts to increase the 53 weight and space requirements. It further functions to provide for ready access to the upper levels of the tower structure as may be required.

Having described my invention and the best mode of constructing the same, what I consider to be my invention is set forth in the following claims.

I claim:

1. A collapsible tower section comprising a first and third side each having a pair of parallel members, transverse parallel members connecting the corresponding ends of said parallel members and diagonal struts connecting said parallel members intermediate said transverse parallel members, a second side comprising diagonal strut members having means hingedly connecting opposite ends thereof to one parallel member of each of said first and third sides thereby permitting said first and third sides to be folded against said second side, a fourth side comprising separately removable diagonal strut members, each strut member having means on the end thereof for releasably embracing the other parallel member of each of said first and third sides and means on said parallel members preventing motion of said means longitudinally of said parallel members, a platform providing a top side for said tower section designed to stiffen said section against horizontal shearing forces comprising a pair of transverse members having means to engage the top transverse parallel members of said first and third sides of said tower section, spreader members eX- tending between said transverse members forming with said transverse members a peripheral boundary for said platform, diagonal strut members connecting the midportion of each transverse member to the mid-portion of said spreader members and forming a boundary of an access opening through said platform and grating means extending between said peripheral boundary and said strut members to form a flooring for said top side and slanting ladder means having means at each end thereof for engaging and embracing a strut member of said platforms and a strut member of a platform of a preceding tower section to provide access between levels of said tower section and to internally strengthen the tower structure.

2. A collapsible tower section comprising a first and third side, each formed by a pair of spaced parallel members, transverse members connecting the corresponding ends of said spaced parallel members, and diagonal strut members connecting said spaced parallel members at points between said transverse members, a second side formed of a plurality of diagonal strut members having means on the ends thereof embracing a parallel member of each of said first and third sides and pivoted thereabout to permit the first and third sides to be folded against said second side, a fourth side formed by a plurality of removable diagonal strut members means on the ends thereof for releasably connecting said removable diagonal strut members to the other of said spaced parallel members, a platform comprising spreader members releasably engaging at opposite ends thereof a transverse member of each said first and third sides, side members connecting the corresponding ends of said spreader members, said spreader and side members forming a peripheral boundary of said platform, diagonal gusset members connecting the mid-portion of said spreader members to the mid-portion of said side members, said diagonal gusset members forming a framing for an access opening through said platform, and expanded metal grating connected to said peripheral boundary and said framing to constitute a flooring for said platform and a slanting ladder having means at each end thereof for engaging the diagonal gusset members of said platform and a platform of an adjacent tower section to provide access between the said platforms and to form an internal strut member for said tower section.

3. A portable tower for supporting an antenna comprising a plurality of tower sections, mounted one upon another in a vertical direction to a prescribed height, each tower section comprising a first and third side each formed by a pair of spaced parallel members, transverse members connecting the corresponding ends of said spaced parallel members and diagonal strut members connecting said spaced parallel members at points between said transverse members, a second side formed of a plurality of diagonal strut members having means on the ends thereof for embracing a parallel member of each of said first and third sides and pivoted thereabout to permit the first and third sides to be folded against said second side, a fourth side formed by a plurality of removable diagonal strut members means on the ends thereof for releasably connecting said removable diagonal strut members to the other of said spaced parallel members, a platform located at the top of each tower section and forming the bottom of the succeeding tower section comprising spreader vmembers having means thereon for releasably engaging at opposite ends thereof a transverse member on each of said first and third sides, side members connecting the corresponding ends of said spreader members said spreader and side members forming a peripheral boundary means of said platform, diagonal gusset members connecting the mid-portion of said spreader members to the mid-portion of said side members said diagonal gusset members forming a framing means for an access'opening through said platform, and an expanded metal grating connected to and extending between said boundary and framing means to constitute a flooring for said platform and slanting ladder means connected to the gusset members of the platforms of adjacent tower sections to provide access between platforms and to act as an internal strut for said tower.

References Cited in the file of this patent UNITED STATES PATENTS 2,267,658 Larsen Dec. 23, 1941 2,665,950 Johnson Jan. 12, 1954 2,720,430 Meng et al. Oct. 11, 1955 FOREIGN PATENTS 800,787 Germany Dec. 7, 1950 

